Leroy v



May 19, 1931. v, CRAM 1,806,539

FAN

Filed Nov. 4, 1926 zjwuentov Patented May 19, 1931 UNITED STATES PATENT orrica LEROY v. CRAM, or FLINT, MICHIGAN, AssIGnoR To. GENERAL MoTo IsoonI'onATIou or DETROIT, MICHIGAN, A CQBBQRATION or DELAWARE.

FAN-' Application filed November 4; 1926. Serial No. 146,205;

vibrate at certain speeds, setting up disagree able humor noise. The present invention contemplates the elimination of such vibra- 1p tory noises, by making the fan of laminated sheet metal and so arranging the structure as to afford a fan of increased strength, whereby tendency toward wing tip distortion 18 overcome, without material difference In cost of 1,3 manufacture or variation in the weight or mass of metal of similar fans now on the market.

Referring to the accompanying drawings, wherein is shown a preferred but not necessarily the only form of the invention, Figure 1 is a side elevation of the present fan structure, as it would be mounted for rotation at the front of an explosive engine. Figure 2 is a front plane view of the fan. Figure 3 is an end view, looking in the direction of the arrows on line 33 in Figure 2. Figure 4 is a section taken on line 4-4 of Figure 2.

In the drawings, a double blade-d fan is shown, consisting of a fiat hub portion 1, and

a single pair of oppositely disposed angularly curved blades or vanes 22. The hub 1 1s provided with a central circular opening or hole 3, to fit over a circular boss 4 on a pulley 5, and bolts 66 extending thru the openings 7-7 in the fan hub l, anchor the fan to the pulley 5. The pulley is rotatably mounted at the front of the engine block 8, and is driven by the belt 9, from an engine shaft in the usual manner. Longitudinal 4o corrugations 10 may be provided to strengthen and stiffen the fan blades.

Fans of this general character are ordinarily made from a single piece of sheet metal. In the present instance, it is proposed to constru'ct the fan of two or more layers of light gage sheet metal, of uniform area and integrally united in superposed relation and in registry with each other, to form a laminated fan structure of approximately the same thickness as these heretofore employed In the same radial plane.

constructingthe fan, the stamped blanks, are aligned one on top oftheother, sothat correspondingbladesQf successive plates are in A preferred manner of integrally uniting the several sheets, is to spot weld at predetermined, points, as indicated by the crosses in Figure 2. In order that the blades onopposite sides of the hub may be equalized, the welds should be located in balanced relation as is shown, andpreferably along the blade edges and tips. The blades are then angularly skewed and con- .cavedon-the air pushing side, leaving the intermediate flat hub portion. 7

From the above description it will beapparentthat there is provided a fan which will be simple and economicalto manufacture, of lightweight but of. sufiicient; stiffness and rigidity to eliminate vibratory noises. IVhile the construction is particularly adapted for radiator fans, it is to be understood that it may be employed in other types of fans, and that obvious modifications of the particular construction described may be made as come within the scope of the appended claims.

Having describcd the invention, I claim:

1. In a cooling system for internal combustion engines of motor vehicles and the like, a fan for inducing an air draft through a cooling radiator, including a laminated blade in which the laminations consist of relatively thin gauge sheet meta-l'plates of identical shape and outline thruout superposed on one another and integrally united in alined relation with one face of one plate in continuous contact from tip to tip with the adjacent face of the other.

2. In a'cooling system for internal combustion engines of motor vehicles and the like, a fan for inducing an air draft through a cooling radiator, including a number of identical plates, each having a flat hub and a series of angularly curved blades, and means to integrally secure said plates together in superposed registry, with one face of one plate in continuous contact from tip to tip with the adjacent face of the other so that corresponding blades of the several plates are combined as a single unit of uniform width and thickness throughout.

3. In a cooling system for internal combustion engines of motor vehicles and the like, a fan for inducing an air draft through a cooling radiator, including a number of duplicate plates, each of substantially uniform area and superposed one on another in registry with one face of one plate in con: tinuous contact from tip to tip With the adjacent face of the other, and having corresponding cooperating corrugations internesting one in another.

4. In a cooling system for internal oombustion engines of motor vehicles and the like, a fan for inducing an air draft through a cooling radiator, including blades comprised of superposed duplicate plates arranged in alined registry with each plate extending to the tip of the blade in continuous face to face contact with the next plate.

5. In a cooling system for internal combustion engines of motor vehicles and the like, a fan for inducing an air draft through a cool ing radiator, including blades comprised of superposed duplicate plates arranged in alined registry With each plate extending to the tip of the blade in continuous face to face contact with the next plate, and a projection on one plate extending in interlocking relation into a corresponding depression in the next succeeding plate.

In testimony whereof I afiix my signature.

LEROY v. CRAM. 

